VB -> C#: Action lambda breaks

[docfresh]

Error thrown by compiler on erroreous code is "Delegate Action<UserPopup> does not take 0 arguments" (CS1593)

VB.Net input code

    Private Sub btnFilter_Click(sender As Object, e As EventArgs) Handles btnFilter.Click
        upMCIF.Height = Me.Height - Me.Panel1.Height - 20
        upMCIF.Width = Me.Width - 20


        upMCIF.ShowPopup(8, Me.Panel1.Height, Sub()
                                                  'upMCIF.Height = 1
                                                  'upMCIF.Width = 1
                                                  Me.SetFilters()
                                                  Me.Focus()
                                                  btnFilter.Refresh()
                                                  btnFilter.Invalidate()
                                                  btnFilter.Update()

                                              End Sub)
        upMCIF.Focus()
    End Sub

Erroneous output

private void btnFilter_Click(object sender, EventArgs e)
        {
            upMCIF.Height = Height - Panel1.Height - 20;
            upMCIF.Width = Width - 20;
            upMCIF.ShowPopup(8, Panel1.Height, () =>
            {
                // upMCIF.Height = 1
                // upMCIF.Width = 1
                SetFilters();
                Focus();
                btnFilter.Refresh();
                btnFilter.Invalidate();
                btnFilter.Update();
            });
            upMCIF.Focus();
        }

Expected output

//Unsure of what the right code should be, but this would compile.

private void btnFilter_Click(object sender, EventArgs e)
        {
            upMCIF.Height = Height - Panel1.Height - 20;
            upMCIF.Width = Width - 20;

            upMCIF.ShowPopup(8, Panel1.Height, (onclose) =>
            {
                // upMCIF.Height = 1
                // upMCIF.Width = 1
                SetFilters();
                Focus();
                btnFilter.Refresh();
                btnFilter.Invalidate();
                btnFilter.Update();
            });

            upMCIF.Focus();
        }

Details

CC 8.41 vs2019 extension

Signature of ShowPopup is

    public void ShowPopup(int x, int y, Action<UserPopup> onclose = null);

[GrahamTheCoder]

Thanks, I'm pretty sure the converter has some code to deal with this case already, will have to investigate why it's not working in this case